PRESCOTT – Described as an “effective tool” for improving intersection safety and moving traffic, roundabouts got a positive review by the Prescott City Council this week.

BY THE NUMBERS

• 90% reduction in fatal crashes

• 75% reduction in injury crashes

• 30-40 percent reduction

in pedestrian crashes

• 10% reduction in

bicycle crashes

• 30-50% increase

in traffic capacity

— Insurance Institute of Highway Safety

During their Tuesday, Oct. 25 study session, council members heard a presentation from the city’s public works department on roundabouts – the traffic circles that are used as alternatives to traffic signals.

Prescott Traffic Engineer Ian Mattingly maintained that roundabouts offer a “safer choice” – in part, because of slower entry points to the intersection, and a reduction in the number of conflict points.

Because of that, Mattingly said, the number of accidents is reduced, as well as the severity of the collisions.

While Tuesday’s discussion was informational, and not intended for a vote, council members appeared supportive of the continued use of roundabouts in the city’s transportation system.

Councilman Steve Blair, for instance, pointed out that the planned roundabout at Highway 89 and the Phippen Museum would help to slow down traffic as the highway transitions from a five-lane road to the north to a two-lane road south through the Granite Dells area.

“From my standpoint, the majority of the reason for putting it in is public safety, which means slowing speeds down,” Blair said, “because there’s a major road infrastructure change when you go through the Granite Dells area.”

Council members also offered suggestions for making the roundabouts more visible to drivers.

Councilwoman Jean Wilcox noted that public art in the center of the roundabout could help to alert drivers to the existence of the roundabouts, as well as to beautify the area.

“I think Chino Valley has done a wonderful job of putting public art in the roundabouts,” Wilcox said. “You see them from a long ways off, so you know you’re coming to something in the middle of the road.” She added, “I think it would be an entirely appropriate use of the streets fund to put public arts in the roundabouts.”

While the city has studied a number of locations for possible roundabouts, Mattingly said, “Every location is not appropriate for roundabouts.”

For example, he said the city looked at the Prescott Lakes Parkway/Blooming Hills Drive as a possible location for a roundabout, but ultimately determined that the intersection did not have adequate sight distance for a roundabout. “It was immediately eliminated because it wasn’t a good fit,” Mattingly said. (The city recently installed a traffic signal at the corner).

While the Highway 89/Phippen Museum intersection plans have raised concerns in the community, Mattingly emphasized that the roundabout did not drive the plans. “The impetus for the improvement, while it seems to be focused on the roundabout, is not really the roundabout,” he said.

Rather, Mattingly said, the roundabout makes up about $800,000 to $1 million of a $3.5 million city project that includes widening the highway and improving the access to the Phippen Museum and the nearby Constellation Trail.

“(The city project) will provide the last section of widening (of Highway 89) all the way from Chino Valley,” Mattingly said, referring to the Arizona Department of Transportation’s (ADOT) on-going widening project.

A TIP FROM ADOT

Never merge. The right of way is observed at the yield sign. Motorists already in the roundabout have the right of way. You must slow down or stop to yield to traffic approaching from the left. Wait for a gap in traffic, then carefully proceed into the roundabout.

In addition, Mattingly said, the intersection was needed as an access point for the future Side Road Connector – a “regional road, identified in the (Central Yavapai Metropolitan Planning Organization’s) 2040 transportation plan.”

The Phippen-area intersection will be one of two new roundabouts planned for Highway 89, Mattingly said, noting that ADOT also plans a roundabout at Perkins Drive as a part of its upcoming Highway 89 widening near the Prescott Airport.